[EMAIL PROTECTED] wrote:
Vortexians- The evening news on ABC ststed that the clock watchers are going to add a leap second to the last second of Dec.31,2005 to correct the clocks to the earths rotation. It seems that they have had to add 23 seconds since1972 to correct clocks. The Earth has been slowing down its rotation speed. The slowing of the earth should increase its temperature I would think (Im possibly wrong.) It does seem to coinside with the years of biggest increase of temperature. Or as many suspect just a normalcycle. A cycle we are not aware of. _ges-
My understanding is that the slowing of the Earth is due to tidal forces exerted on the Earth by the Moon.
In simple Newtonian terms, the tital bulge of the ocean isn't directly under the moon -- it's "dragged" by the rotation of the earth to a position a number of degrees off from where you'd expect (high tide isn't when the Moon is at the zenith, as you might have expected). In consequence, the shape of the earth "seen" by the Moon's gravitational field isn't a sphere, and the Moon's gravity actually exerts a torque on the Earth. In turn, the Earth exerts an off-center force on the Moon, which is consequently gradually being "spun up" in its orbit. The Moon's orbit gets bigger, and the Earth slows down simultaneously.
Another way to look at it is that the oceans are dragged around the Earth by the tides in the opposite directly from its rotation, and friction between the oceans and their beds is gradually slowing down the Earth. It's a little harder to see how energy and angular momentum are conserved when viewing it this way, tho.
Either way, this has been going on at roughly the same rate for as long as there have been liquid oceans on the Earth. So, while it's no doubt contributing some amount of heat to the Earth, it's not a new effect; the current unusual warming of the Earth surely is unrelated to it.
